Arri Priimägi

Shape-changing polymers leading to a paradigm shift in soft robotics

Life-like synthetic materials will shape the future of soft robotics. Before this actually occurs, it is important to examine what we can learn from complex biological processes such as sensory-motor interactions, and how we can transfer the lessons learned into the context of synthetic materials. The MULTIMODAL project aims to develop autonomous and interactive materials that adapt to different environments, can be trained to perform specific actions, self-heal, and make simple decisions similar to those made by living organisms. The project uses liquid crystal elastomers – polymer materials that can transform their morphology and properties in response to external stimuli. The developed parts will be used to design soft robots with autonomous and interactive properties.

A new photonics era: controlling light with light-induced mechanical deformations

The field of photonics was born six decades ago with the development of lasers. Over the years, advances in photonics have revolutionised numerous fields, including communications, energy, biomedicine, and space exploration. The PHOTOTUNE project pioneered the evolution in photonics with a comprehensive toolbox for light-tunable solid-state photonics based on photoactuable liquid-crystal elastomers. These materials display large light-induced deformations through coupling between anisotropic liquid-crystal order and elasticity in the polymer network. They were then used in films to create lasers tunable by light and to fabricate metal nanostructures on substrates that can contract and expand in response to light.

Results

The projects focus on materials in which light energy can be converted into mechanical motion. These materials demonstrate the power of light and light-responsive molecules, paving the way also for new technologies. The goal of PHOTOTUNE was to harness them for applications in photonics. Work in this area is underway, and as spin-offs, the team has launched three ERC proof-of-concept projects on sensing, photocontrollable cell growth, and AR/VR technologies. The project also resulted in advancements in light-driven small-scale soft robotics, spawning the ideas that emerged as the MULTIMODAL project.

MULTIMODAL can be categorised under “life-inspired” materials. The team tries to learn from biological systems (functions of cells, adaptation of plants, processes such as self-healing or learning) and mimic those characteristics in synthetic, light-responsive materials. It is a curiosity-driven, blue-skies research that in longer term will affect sustainable materials development and applications sprouting therein.

Impact

Priimägi believes that the biggest impact of this research does not come through potential applications but through hopefully stimulating the scientific community and inspiring other researchers (publications on the subject are well-cited). He also hopes it will be inspiring and provide a training ground for next-generation scientists, who might one day change the world with what they do. He hopes the project will attract the attention of a broader audience, as the work is very visual and hopefully attractive for non-scientists and youngsters considering a scientific career. Science has value on its own, and potential applications follow as a side product.